2 files changed, 56 insertions, 0 deletions

diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index f6270ee..e5cf26e 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -15,6 +15,7 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/gpio.h>
+#include "../../gpio/gpiolib.h"
 #include <linux/of_gpio.h>
 
 struct gpiomux {
@@ -137,6 +138,7 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
 	struct i2c_mux_core *muxc;
 	struct gpiomux *mux;
 	struct i2c_adapter *parent;
+	struct i2c_adapter *root;
 	unsigned initial_state, gpio_base;
 	int i, ret;
 
@@ -184,6 +186,9 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, muxc);
 
+	root = i2c_root_adapter(&parent->dev);
+
+	muxc->mux_locked = true;
 	mux->gpio_base = gpio_base;
 
 	if (mux->data.idle != I2C_MUX_GPIO_NO_IDLE) {
@@ -194,6 +199,9 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
 	}
 
 	for (i = 0; i < mux->data.n_gpios; i++) {
+		struct device *gpio_dev;
+		struct gpio_desc *gpio_desc;
+
 		ret = gpio_request(gpio_base + mux->data.gpios[i], "i2c-mux-gpio");
 		if (ret) {
 			dev_err(&pdev->dev, "Failed to request GPIO %d\n",
@@ -210,8 +218,18 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
 			i++;	/* gpio_request above succeeded, so must free */
 			goto err_request_gpio;
 		}
+
+		if (!muxc->mux_locked)
+			continue;
+
+		gpio_desc = gpio_to_desc(gpio_base + mux->data.gpios[i]);
+		gpio_dev = &gpio_desc->gdev->dev;
+		muxc->mux_locked = i2c_root_adapter(gpio_dev) == root;
 	}
 
+	if (muxc->mux_locked)
+		dev_info(&pdev->dev, "mux-locked i2c mux\n");
+
 	for (i = 0; i < mux->data.n_values; i++) {
 		u32 nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0;
 		unsigned int class = mux->data.classes ? mux->data.classes[i] : 0;
diff --git a/drivers/i2c/muxes/i2c-mux-pinctrl.c b/drivers/i2c/muxes/i2c-mux-pinctrl.c
index f4e62f4..35bb775 100644
--- a/drivers/i2c/muxes/i2c-mux-pinctrl.c
+++ b/drivers/i2c/muxes/i2c-mux-pinctrl.c
@@ -24,6 +24,7 @@
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/of.h>
+#include "../../pinctrl/core.h"
 
 struct i2c_mux_pinctrl {
 	struct i2c_mux_pinctrl_platform_data *pdata;
@@ -120,10 +121,31 @@ static inline int i2c_mux_pinctrl_parse_dt(struct i2c_mux_pinctrl *mux,
 }
 #endif
 
+static struct i2c_adapter *i2c_mux_pinctrl_root_adapter(
+	struct pinctrl_state *state)
+{
+	struct i2c_adapter *root = NULL;
+	struct pinctrl_setting *setting;
+	struct i2c_adapter *pin_root;
+
+	list_for_each_entry(setting, &state->settings, node) {
+		pin_root = i2c_root_adapter(setting->pctldev->dev);
+		if (!pin_root)
+			return NULL;
+		if (!root)
+			root = pin_root;
+		else if (root != pin_root)
+			return NULL;
+	}
+
+	return root;
+}
+
 static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
 {
 	struct i2c_mux_core *muxc;
 	struct i2c_mux_pinctrl *mux;
+	struct i2c_adapter *root;
 	int i, ret;
 
 	mux = devm_kzalloc(&pdev->dev, sizeof(*mux), GFP_KERNEL);
@@ -202,6 +224,22 @@ static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
 		goto err;
 	}
 
+	root = i2c_root_adapter(&muxc->parent->dev);
+
+	muxc->mux_locked = true;
+	for (i = 0; i < mux->pdata->bus_count; i++) {
+		if (root != i2c_mux_pinctrl_root_adapter(mux->states[i])) {
+			muxc->mux_locked = false;
+			break;
+		}
+	}
+	if (muxc->mux_locked && mux->pdata->pinctrl_state_idle &&
+	    root != i2c_mux_pinctrl_root_adapter(mux->state_idle))
+		muxc->mux_locked = false;
+
+	if (muxc->mux_locked)
+		dev_info(&pdev->dev, "mux-locked i2c mux\n");
+
 	for (i = 0; i < mux->pdata->bus_count; i++) {
 		u32 bus = mux->pdata->base_bus_num ?
 				(mux->pdata->base_bus_num + i) : 0;